Aruba Remote Access Point (RAP) Networks. Version 8

Transcription

1 Aruba Remote Access Point (RAP) Networks Version 8

2 Copyright 2012 Aruba Networks, Inc. AirWave, Aruba Networks, Aruba Mobility Management System, Bluescanner, For Wireless That Works, Mobile Edge Architecture, People Move. Networks Must Follow, RFprotect, The All Wireless Workplace Is Now Open For Business, Green Island, and The Mobile Edge Company are trademarks of Aruba Networks, Inc. All rights reserved. Aruba Networks reserves the right to change, modify, transfer, or otherwise revise this publication and the product specifications without notice. While Aruba uses commercially reasonable efforts to ensure the accuracy of the specifications contained in this document, Aruba will assume no responsibility for any errors or omissions. Open Source Code Certain Aruba products include Open Source software code developed by third parties, including software code subject to the GNU General Public License ( GPL ), GNU Lesser General Public License ( LGPL ), or other Open Source Licenses. The Open Source code used can be found at this site: Legal Notice ARUBA DISCLAIMS ANY AND ALL OTHER REPRESENTATIONS AND WARRANTIES, WEATHER EXPRESS, IMPLIED, OR STATUTORY, INCLUDING WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, NONINFRINGEMENT, ACCURACY AND QUET ENJOYMENT. IN NO EVENT SHALL THE AGGREGATE LIABILITY OF ARUBA EXCEED THE AMOUNTS ACUTALLY PAID TO ARUBA UNDER ANY APPLICABLE WRITTEN AGREEMENT OR FOR ARUBA PRODUCTS OR SERVICES PURSHASED DIRECTLY FROM ARUBA, WHICHEVER IS LESS. Warning and Disclaimer This guide is designed to provide information about wireless networking, which includes Aruba Network products. Though Aruba uses commercially reasonable efforts to ensure the accuracy of the specifications contained in this document, this guide and the information in it is provided on an as is basis. Aruba assumes no liability or responsibility for any errors or omissions. ARUBA DISCLAIMS ANY AND ALL OTHER REPRESENTATIONS AND WARRANTIES, WHETHER EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, NONINFRINGEMENT, ACCURACY, AND QUIET ENJOYMENT. IN NO EVENT SHALL THE AGGREGATE LIABILITY OF ARUBA EXCEED THE AMOUNTS ACTUALLY PAID TO ARUBA UNDER ANY APPLICABLE WRITTEN AGREEMENT OR FOR ARUBA PRODUCTS OR SERVICES PURCHASED DIRECTLY FROM ARUBA, WHICHEVER IS LESS. Aruba Networks reserves the right to change, modify, transfer, or otherwise revise this publication and the product specifications without notice Crossman Avenue Sunnyvale, California Phone: Fax Aruba Networks, Inc. 2

3 Table of Contents Chapter 1: Introduction 8 Reference Material 9 Icons Used in this Guide 10 Chapter 2: Virtual Branch Networks 11 Aruba Virtual Branch Network Solution 11 Chapter 3: Remote Deployments 13 Logical Architecture of Aruba Remote Networks 15 RAP Operation 18 Key Components of the Architecture 19 Master Controllers 19 RAPs 20 AMs 20 Firewall Ports 20 Chapter 4: All-Master Design for Remote Networks 21 Controller Licenses 21 Licensing Master Mobility Controllers 21 Certificates 22 Chapter 5: VLAN Design and Recommendations 23 VLAN Pooling 25 Chapter 6: Redundancy 27 Master Redundancy 27 Chapter 7: Configuring VPN Server on the Controller 37 Configuring the VPN Server on the Controller 37 RAP Bootstrapping 37 VPN Server Configuration 38 Configuring the VPN Authentication Profiles 42 Chapter 8: Configuring AP Group for RAPs 45 Alias 46 Configuration Profiles 47 AP Groups 48 Aruba Networks, Inc. Table of Contents 3

4 Chapter 9: Fixed Telecommuter Solution 50 Requirements of Fixed Telecommuter Solution 50 Creating AP Group for RAPs in Fixed Telecommuter Deployments 50 Chapter 10: Configuring the Remote Employee Role 52 Configuring the common-dhcp Policy 53 Configuring the sip-session-allow Policy 54 Configuring the remote-employee Policy 56 Configuring the remote-employee Role 57 Chapter 11: Remote Employee VAP 59 Forwarding Modes 60 Tunnel Mode 60 Split-Tunnel Mode 60 Bridge Mode 61 Decrypt-Tunnel Mode 61 RAP Operation Modes 61 AP/AM Data and Control Tunnels 62 RAP/AP Tunnels 62 Remote Employee SSID Profile 63 Configuring the Remote Employee SSID Profile 64 Configuring Wi-Fi Multimedia 64 Configuring the Remote Employee AAA Profile 67 Authentication Server and Server Groups 67 Configuring the Server Group for 802.1X Authentication 68 Configuring the Remote Employee AAA Profile 70 Configuring the Remote Employee VAP Profile 73 Chapter 12: Configuring the Guest Role and VAP for Fixed Telecommuter Deployment 75 Configuring the guest-home-access Policy 76 Configuring the Guest Role for Fixed Telecommuter Deployments 77 Configuring the Guest SSID for Fixed Telecommuter Deployments 78 Configuring the Guest AAA Profile for Fixed Telecommuter Deployments 80 Configuring the Guest VAP Profiles for Fixed Telecommuter Deployments 82 Chapter 13: Micro Branch Office Solution 84 Requirements of Micro Branch Office Deployments 84 Creating AP Group for RAPs in Micro Branch Office Deployments 84 Remote Employee Role and VAP Profile for Micro Branch Office Deployments 85 Aruba Networks, Inc. Table of Contents 4

5 Chapter 14: Configuring the Guest Roles and VAP Profile for Micro Branch Office Deployments 86 Configuring the clearpass-guest Policy 88 Configuring the guest-branch-logon-access Policy 90 Configuring the block-internal-access Policy for the Guest Role 91 Configuring the auth-guest-access Policy 92 Configuring the drop-and-log Policy 94 Configuring the Initial Guest Role 95 Configuring the Authenticated Guest Role 96 Maximum User Sessions for Guest Role 98 Configuring the Guest SSID Profile for Micro Branch Office Deployments 100 Configuring the Server Group for Guest Authentication 101 Configuring the Captive Portal Authentication Profile for Guest WLAN 102 Configuring the Guest AAA Profile for Micro Branch Office Deployments 105 Configuring the Guest VAP Profile for Micro Branch Office Deployments 106 Chapter 15: Configuring the Radio Profiles 108 Configuring the ARM Profile 108 Configuring the a and g Radio Profiles 113 Chapter 16: Configuring the AP System Profiles 116 RF Band 116 Native VLAN and Remote-AP DHCP Server 117 RAP Uplink Bandwidth Reservation 119 Configuring the Uplink Bandwidth Reservation 120 Remote-AP Local Network Access 122 Corporate DNS Domain 123 Configuring the AP System Profile 124 Chapter 17: Configuring the QoS 127 Chapter 18: RAP Wired Ports 128 Configuring the Wired AP Profile 129 AAA Profile for Wired Ports 132 Remote Application Role 132 Configuring the tftp-session-allow Policy 132 Configuring the Remote Application Role 133 Corporate AAA Profile for Wired Ports 134 Guest AAA Profile for Wired Ports 138 Aruba Networks, Inc. Table of Contents 5

6 AP Wired Port Profile 139 Wired Ports for Printer in Micro Branch Office Deployments 141 Disabling the Wired Ports 142 Chapter 19: RAP 3G Uplink 144 Chapter 20: Configuring the AP Group for Telecommuter and Micro Branch Office Deployments 149 AP-Specific Configuration 153 Chapter 21: AP Group for Dedicated Air Monitors 155 Configuring the AM Scanning Profile 156 Configuring the a and g Radio Profiles 158 Configuring the AP Groups for Air Monitors 160 Chapter 22: Fallback/Backup Mode for Wireless SSIDs and Wired Ports 162 Chapter 23: Wireless Intrusion Prevention (IDS Profiles) of RFProtect 166 Chapter 24: Spectrum Analysis 172 Chapter 25: RAP Provisioning 176 Zero-Touch Provisioning 176 IT Team Tasks for Zero-Touch Provisioning 176 Onsite Tasks for Zero-Touch Provisioning 177 Preprovisioning 179 IT Team Tasks for Preprovisioning 179 Onsite Tasks for Preprovisioning 181 Onsite RAP Deployment 181 Chapter 26: Wide-Area Network Considerations 182 Bandwidth Constraints 182 Latency Constraints 182 3G Wireless Constraints 183 Recommendations for Minimizing Constraints 183 Chapter 27: Logging 185 Chapter 28: AirWave 188 WMS Offload 189 Chapter 29: ClearPass Guest 190 Aruba Networks, Inc. Table of Contents 6

7 Appendix A: Regulatory Compliance 191 Regulatory Compliance for International Deployments 191 AP Compliance 191 Controller Compliance 191 Recommendations for International Deployments 192 Appendix B: RAP Control Traffic 193 Appendix C: Geographical Redundancy for RAP Deployments 194 Geographical Redundancy Design 194 Geographical Redundancy for Global RAP Deployments 197 Recommendations for Geographical Redundancy 198 Appendix D: Broadcast and Multicast Mitigation Features 201 Broadcast-filter ARP (Global Firewall Knob) 201 Drop Broadcast and Multicast (VAP Knob) 203 Convert Broadcast ARP Requests to Unicast (VAP Knob) 204 Broadcast (Wired AP Knob) 205 Suppress-ARP (VLAN Knob) 207 BC-MC Optimization (VLAN Knob) 208 Local-proxy-ARP (VLAN Knob) 209 Appendix E: Contacting Aruba Networks 213 Contacting Aruba Networks 213 Aruba Networks, Inc. Table of Contents 7

8 Chapter 1: Introduction The Aruba (VRD) series is a collection of technology deployment guides that include descriptions of Aruba technology, recommendations for product selections, network design decisions, configuration procedures, and best practices for deployment. Together these guides comprise a reference model for understanding Aruba technology and designs for common customer deployment scenarios. Each Aruba VRD network design has been constructed in a lab environment and thoroughly tested by Aruba engineers. Our customers use these proven designs to rapidly deploy Aruba solutions in production with the assurance that they will perform and scale as expected. The VRD series focuses on particular aspects of Aruba technologies and deployment models. Together the guides provide a structured framework to understand and deploy Aruba wireless LANs (WLANs). The VRD series has four types of guides: Foundation: These guides explain the core technologies of an Aruba WLAN. The guides also describe different aspects of planning, operation, and troubleshooting deployments. Base Design: These guides describe the most common deployment models, recommendations, and configurations. Applications: These guides are built on the base designs. These guides deliver specific information that is relevant to deploying particular applications such as voice, video, or outdoor campus extension. Specialty Deployments: These guides involve deployments in conditions that differ significantly from the common base design deployment models, such as high-density WLAN deployments. Specialty Deployments Applications Base Designs Foundation arun_0334 Figure 1 VRD Core Technologies This guide covers the deployment of Aruba remote access points (RAP) in fixed telecommuter and micro branch office sites, and it is considered part of the base designs guides within the VRD core technologies series. This guide covers the design recommendations for remote network deployment and it explains the various configurations needed to implement a secure, high-performance virtual branch office (VBN) solution with Aruba RAPs. Aruba Networks, Inc. Introduction 8

9 This guide describes these specific topics: recommended remote network design controller redundancy and licensing VLAN design for remote networks configuration of AP groups for fixed telecommuter and micro-branch office deployments RAP provisioning Table 1 lists the current software versions for this guide. Table 1 Product Aruba Software Versions Version ArubaOS (mobility controllers) 6.1 ArubaOS (mobility access switch) 7.1 Aruba Instant 1.1 MeshOS 4.2 AirWave 7.5 ClearPass Guest (AmigopodOS) 3.9 Reference Material This guide is a base designs guide, and therefore it will not cover the fundamental wireless concepts. This guide helps a wireless engineer configure and deploy the Aruba RAP solution. Readers should have a good understanding of wireless concepts and the Aruba technology that are explained in the foundation-level guides. For information on indoor MIMO WLANs, see the Aruba n Networks Validated Reference Design, available on the Aruba website at For information on Aruba Mobility Controllers and deployment models, see the Aruba Mobility Controllers and Deployment Models, available on the Aruba website at For specific deployment configuration details, or for deployment models for a/b/g networks, see the 3.X series of VRDs on the Aruba website at vrd/. The existing VRDs will be updated to follow this new format. The complete suite of Aruba technical documentation is available for download from the Aruba support site. These documents present complete, detailed feature and functionality explanations beyond the scope of the VRD series. The Aruba support site is located at: This site requires a user login and is for current Aruba customers with support contracts. For more training on Aruba products or to learn about Aruba certifications, visit the Aruba training and certification page on our website. This page contains links to class descriptions, calendars, and test descriptions: Aruba Networks, Inc. Introduction 9

10 Aruba hosts a user forum site and user meetings called Airheads Social. The forum contains discussions of deployments, products, and troubleshooting tips. Airheads Online is an invaluable resource that allows network administrators to interact with each other and Aruba experts. Announcements for Airheads in person meetings are also available on the site: The VRD series assumes a working knowledge of Wi-Fi, and more specifically dependent AP, or controller based, architectures. For more information about wireless technology fundamentals, visit the Certified Wireless Network Professional (CWNP) site at Icons Used in this Guide Figure 2 shows the icons that are used in this guide to represent various components of the system. AP Air monitor Spectrum monitor Switch Mobility controller Laptop Router Server AirWave server ClearPass Microwave Mobile phone Firewall Network cloud Wired phone Desktop computer Printer PSP / gaming console arun_1078 Figure 2 VRD icon set Aruba Networks, Inc. Introduction 10

11 Chapter 2: Virtual Branch Networks Users who work from locations other than the organization s primary campus, headquarters facility, or large regional office are called remote users. Remote users typically work from home offices, small satellite offices, medium-sized branch offices, or on the road from hotels, hot spots, or customer locations. Each of these remote locations has different connectivity, capacity, and usage requirements. In general, we can categorize the remote deployments as follows: Fixed telecommuter deployment: a remote worker at home with a few devices Micro branch office deployment: a branch office that can be served with a single AP and a few wired ports Small and medium branch office deployment: a branch office with less than 250 devices Large or regional branch office deployments: a branch office with 250 or more devices and with more complex requirements than a traditional branch office Mobile access: secure access to a single device, such as a laptop, by using a virtual private network (VPN) client IT organizations traditionally have served each category using a different remote network architecture. For example, micro branches used a branch office router to interconnect an IP subnet at the remote site to the corporate network core, while telecommuters with only a single PC or laptop could be served with a software VPN client. Branch office routers may have been acceptable when there were few mobile workers or mobile devices, however, today s proliferation of mobile devices and users renders them too costly and complex to be satisfactory. Aruba remote network solutions blend the simplicity of a centralized network-based VPN with the flexibility of sophisticated role-based access control to deliver a solution that is economical to deploy and easy to support. Aruba Virtual Branch Network Solution The Aruba virtual branch network (VBN) architecture delivers comprehensive IP network services to multidevice and multiuser sites and is simpler to deploy, use, and maintain than the simplest of software VPN solution available in the market. VBN includes four primary components: Remote access points (RAPs) extend the corporate LAN to any remote location by enabling seamless wired or wireless data and voice wherever a user finds an Internet-enabled Ethernet port or 3G cellular connection. RAPs are ideally suited for micro remote offices, home offices, telecommuters, mobile executives, and for business continuity applications. The Virtual Internet Access (VIA) client for PCs and laptops is a hybrid IPsec/SSL VPN that scans network connections and automatically establishes a VPN connection back to the corporate if the user is connected to an untrusted network. VIA offers a zero-touch end-user experience just plug and play and removes the complexity associated with configuring VPN clients on end user devices. The Aruba Instant solution uses the virtual controller technology embedded in a standard access point (AP) to create a campus or remote wireless network. Stateful redundancy and enterprise- Aruba Networks, Inc. Virtual Branch Networks 11

12 grade security and performance make Aruba Instant ideal for small, medium and even large sized branch offices. The remote node solution serves the needs of large branch and regional offices. With this solution, the deployment of branch office controllers is as simple as the zero-touch RAP provisioning model. Simply enter the fully qualified domain name (FQDN) of the remote node master controller located at the headquarters, and the remaining provisioning is handled automatically. Aruba Networks, Inc. Virtual Branch Networks 12

13 Chapter 3: Remote Deployments The Aruba RAP and VIA solutions cater to the needs of all fixed telecommuter, micro, and mobile access deployments. In these deployments, the Aruba VIA agents and RAPs typically terminate on the master mobility controllers in the network demilitarized zone (DMZ). Similar to the way that campusbased APs and air monitors (AMs) are terminated, the mobility controllers terminate these remote devices coming in over the Internet with IPsec-protected sessions. The Aruba VBN architecture was built to provide high availability. Redundancy may be configured at the controller, at the RAP, or in both places. An all-master design is recommended for remote deployments. For information on other designs such as the master-local design, see the Aruba Mobility Controllers Validated Reference Design. Figure 3 depicts a typical Aruba remote access deployment that provides fixed telecommuter, micro branch office, and mobile access solutions. From data center DMZ Master active Master standby Internet or WAN Fixed telecommuter sites Broadband carrier or 3G EVDO/ GSM carrier Broadband carrier or 3G EVDO/ GSM carrier Micro branch office site Public hotspot Mobile access RAP-5WN RAP-5WN arun_0431 VIA Figure 3 Typical remote deployment with redundancy Aruba Networks, Inc. Remote Deployments 13

14 This VRD explains the design and configuration of the Aruba RAP solution for remote sites that can be served by a single RAP. Figure 4 shows the remote access deployment explained in this VRD. From data center DMZ Master active Master standby Internet or WAN Fixed telecommuter sites Broadband carrier or 3G EVDO/ GSM carrier Broadband carrier or 3G EVDO/ GSM carrier Micro branch office site RAP-5WN RAP-5WN arun_1003 Figure 4 Single RAP deployments CAUTION RAPs should never be deployed in succession. In other words, the uplink port of one RAP should not be connected to the Ethernet port of another RAP to share the WAN uplink. This deployment model is not supported by the Aruba RAP solution. For example, if RAP-1 is connected through RAP-2, the IPsec tunnel of RAP-1 will be formed within the IPsec tunnel of RAP-2 and this causes double encryption and decryption of traffic between the controller and RAP-1. The double IPsec encryption and decryption of traffic affects the performance by increasing the fragmentation and delay. Aruba Networks, Inc. Remote Deployments 14

15 Figure 5 shows the RAP behind a RAP deployment that is not supported by Aruba. Internet or WAN uplink - eth0 RAP-2 eth1 uplink - eth0 RAP-1 arun_1077 Figure 5 RAP behind a RAP (not supported) Logical Architecture of Aruba Remote Networks Figure 6 shows the logical operating model of the Aruba remote network design. Data center AirWave Network services DMZ Network services Aggregation Master active Internet or WAN Management ClearPass Master standby From data center Core switch Network access Fixed telecommuter sites Broadband carrier or 3G EVDO/ GSM carrier Broadband carrier or 3G EVDO/ GSM carrier Micro branch office site Public hotspot Mobile access RAP-5WN RAP-5WN VIA arun_0494 Figure 6 Aruba remote networks logical architecture Aruba Networks, Inc. Remote Deployments 15

16 Aruba remote networks have a logical four-tier operating model that consists of these four layers: Management: The management layer consists of AirWave. AirWave provides a single point of management for the network, including reporting, centralized configuration, and troubleshooting. Network services: The network services layer consists of master mobility controllers and Clearpass. In remote networks, the master mobility controller in the DMZ acts as a hybrid that belongs to the network services and aggregation layers. The master controllers provide a control plane for the Aruba remote networks. The control plane does not directly deal with user traffic or APs. Instead, the control plane provides services such as whitelist coordination, valid AP lists, CPsec certificates, RFProtect coordination, and RADIUS or AAA proxy. ClearPass consists of ClearPass Policy Manager and ClearPass Guest. The ClearPass Policy Manager (CPPM) provides advanced authentication, authorization and accounting (AAA) services and ClearPass Guest offers secure and flexible visitor management services. Aggregation: The aggregation layer is the interconnect point where the AP, AM, spectrum monitor (SM), and VIA traffic aggregates. In remote networks, the master controller in the DMZ act as aggregation layer controller and terminates all the RAPs and VIA. Secure IPsecencrypted, generic route encapsulation (GRE) tunnels from RAPs and VIA terminate on controllers at the aggregation layer. These secure tunnels carry traffic back and forth between the controller and the RAPs. This method provides a logical point for enforcement of roles and policies on remote traffic that enters or exits the corporate LAN. Network access: The network access layer is comprised of RAPs and VIA, which work together with the aggregation layer controllers to overlay the VBN over the WAN. RAPs offer a choice of three different traffic forwarding modes. Tunnel forwarding mode backhauls all traffic to the aggregation layer for processing. When split-tunnel or bridge forwarding modes are used, firewall access control lists (ACLs) in the RAP provide the front line of policy enforcement. All bridge mode traffic with the exception of 802.1X authentication traffic is bridged to the local LAN segment or the Internet and does not reach the aggregation layer. With split-tunnel mode, the traffic destined to the local segment and Internet is bridged locally and only the traffic destined to the corporate network is forwarded to the aggregation layer. RAPs can also serve as AMs and SMs. VIA can operate either in tunnel or split-tunnel forwarding mode. Aruba Networks, Inc. Remote Deployments 16

17 An example network is used to explain the Aruba VBN solution presented in Figure 3. All networks parameters, screenshots, and command line interface (CLI) examples shown in this VRD are from the VRD example network. For details about the network parameters, design, and setup of the entire VRD example network, see the Base Designs Lab Setup for. From data center Core router Internal firewall DMZ rc1-sunnyvale-3600 active rc2-sunnyvale-3600 standby External firewall Simulated internet Fixed telecommuter sites Micro branch office site Mobile access Broadband router Broadband router Broadband router RAP-5WN RAP-5WN arun_0545 VIA Figure 7 VRD example network for remote deployments This VRD describes how to configure these solutions: Fixed telecommuter solution using RAPs: This solution addresses all the needs of telecommuter deployments. It is designed to provide these types of access: Secure wired and wireless access to corporate users and devices by extending the corporate network into employee homes. Local network and Internet access to family members and personal devices Micro branch office solution using RAPs: This solution addresses all the needs of micro branch office deployments. It is designed to provide these types of access: Secure wired and wireless access to corporate users and devices. Internet access (HTTP/HTTPS) to guest users through captive portal authentication. For configuration of mobile hotspot solution using VIA, see the Aruba Virtual Intranet Access (VIA) Application Note. Aruba Networks, Inc. Remote Deployments 17

18 RAP Operation These steps explain how a RAP connects to a controller and how users and devices connect to the corporate network through the RAP. 1. A RAP initiates an IPsec connection to the specified FQDN or public IP address of the controller in the DMZ over any public network. This connection is analogous to the VPN connection initiated by a VPN client on a laptop or desktop to a VPN concentrator. However, for a RAP, there is no single user to be authenticated. Instead, the RAP itself is authenticated on the controller either by using a preprovisioned user name and password on the RAP or by using certificates installed on the RAP. After the RAP is authenticated, the controller assigns an inner IP address to the RAP and an IPsec tunnel is established. 2. A key difference between the Aruba VBN solution and a branch router network is that all configurations are centralized and uploaded to the RAP in real time. No remote configuration is required. After RAP authentication is completed by the controller and the IPsec tunnel has been established, all communication between the controller and the RAP occurs through this secure channel. This encrypted tunnel is now used to download and upgrade the image on the RAP and then to push the RAP configuration from the controller to the RAP. This configuration includes all security settings, firewall roles and policies, wired port policies, and wireless LAN (WLAN) policies. This process is referred to as bootstrapping the RAP. 3. After the RAP has bootstrapped successfully to a controller, the RAP applies the configuration it has received to the wired ports and wireless interfaces. Users and devices can now connect to the wired ports and wireless Service Set Identifiers (SSIDs) configured on the RAP during the bootstrap process. The wired ports and RAPs can be configured to provide role-based access control (RBAC). For information on the authentication and encryption types supported on the ArubaOS, see the Aruba n Networks. The deployment scenario in this VRD portrays the needs of most remote deployments. However, the requirements of each organization are different. Your network may differ from the VRD example network in these ways: VLAN and IP parameters user density and VLAN pools availability, redundancy, and performance requirements type of devices on the network applications running on the network user role requirements authentication and encryption requirements SSID requirements quality of service (QoS) requirements intrusion detection and intrusion prevention requirements mobility requirements network management requirements Adjust the network parameters and Aruba configurations shown in this VRD to meet your needs. Aruba Networks, Inc. Remote Deployments 18

19 Key Components of the Architecture The three key components of this reference model are: master controllers RAPs AMs Master Controllers Depending on the size of the remote deployment, any mobility controller can be chosen as the master controller. The master controllers should be deployed in pairs for redundancy. When controllers like MMC-3600 that does not have redundant power supplies are used as the master controllers, it is recommended that you connect each appliance to discrete power sources. When M3 are used as master controllers, each controller in a redundant pair should have its own MMC-6000 chassis. So, two MMC-6000 chassis can accommodate four pairs of redundant controllers. The MMC-6000 chassis should contain redundant power supplies connected to discrete power sources. CAUTION M3 controllers that are redundant should not be placed in the same chassis, because a chassis failure will cause the redundancy architecture to fail. Selecting the proper mobility controller for the deployment depends on a number of factors, including forwarding mode, usage model, and AP count. Take these factors into account to select the proper mobility controller for the application: AP count user count VIA users forwarding modes data throughput mobility controller role Aruba recommends that VIA and RAP deployments are separated onto different mobility controllers to simplify configuration, deployment, and troubleshooting. When the same controller is used for RAP and VIA termination, the proper calculation of total user count, RAP count, and IPsec tunnels consumed by RAPs/VIA are essential to choose the right controller for your deployment. Remember that the number of supported VIA clients also depends on the configuration of SSL fallback. VIA clients count against the IPsec tunnel limit, but in instances where SSL fallback is enabled, two tunnels must be constructed for each VIA client. For more information on controller selection, see the Aruba Mobility Controllers. Aruba Networks, Inc. Remote Deployments 19

20 RAPs Aruba offers a wide range of n APs. Any AP can be configured as a RAP. However, only devices designated with a RAP part number are capable of zero-touch provisioning. The number of radios available, antenna type, MIMO capability, port density, 3G backup capability, and spectrum capability of the APs vary. NOTE APs such as the AP-9x, AP-105, AP-12x and AP-13x series are designed to be mounted on the ceiling to provide the required coverage. See the Aruba AP product line matrix to choose the most appropriate AP for your deployment. AMs Fixed telecommuter deployments do not require AMs. However, some high-security micro branch office deployments might require dedicated AMs. Dedicated AMs provide full-time surveillance of the air. AMs perform many of the intrusion detection system (IDS) duties for the network, including rogue AP containment. Use the AP-105 as AMs, because these are dual-radio APs with full spectrum analysis support. For details on the spectrum capabilities of all the Aruba APs, see the Aruba AP product line matrix. Firewall Ports RAPs connect to the controller on UDP port 4500 for establishing the IPsec connection. So this port should be opened on all the firewalls leading up to the controllers in the DMZ. Aruba Networks, Inc. Remote Deployments 20

21 Chapter 4: All-Master Design for Remote Networks An all-master design flattens the network hierarchy and is suitable for remote deployments. An allmaster design requires fewer controllers than a master/local design. Though a master/local design is more suitable for campus deployments, the all-master design is the recommended deployment model for remote solutions. In an all-master design, when the network grows past a single pair of redundant controllers, AirWave is recommended. When the WLAN management system (WMS) offload is enabled on the master controllers, AirWave becomes the central point of configuration and monitoring. For information on the limitations of using an all-master design in campus deployments, see the Aruba Mobility Controllers. Controller Licenses The ArubaOS base operating system contains many features and extensive functionality for the WLAN network. Aruba uses a licensing mechanism to enable the additional features and to enable AP capacity on controllers. The controller licensing depends on the AP density and the features needed to operate and secure your network. For more details about Aruba licenses, see Aruba Mobility Controllers and Deployment Models. Licensing Master Mobility Controllers Licensing unlocks the configuration capabilities on the system. Master mobility controllers used in the remote deployment terminate VIA and APs. So the master mobility controller should be licensed based on these two requirements: functionalities required number of devices terminated Only the functionality that is being enabled must be licensed. For example, xsec is deployed primarily only in Federal Government and military installations, and it is not required unless it will be in use at the organization. Master mobility controllers are normally deployed in the active-standby redundancy model, described in Chapter 6: Redundancy. Mobility controllers should be licensed at the maximum expected capacity for that mobility controller. For instance, in a failover scenario, the backup controller must be licensed to accept all the APs that it could potentially host if a failure occurs. As with any system component, it is never a good idea to run the system at maximum capacity and leave no room for future growth. As a general best practice, do not load a controller over 80% of its capacity. In the active-standby redundancy model used for master controllers, the backup master controller should be licensed to the same capacity as the active master controller to accommodate the entire load during failovers. For more information on licensing, see the Aruba Mobility Controllers Validated Reference Design. Aruba Networks, Inc. All-Master Design for Remote Networks 21

22 In the example network, the master controllers in the DMZ are designed for active-standby redundancy. Table 2 lists the licenses that are used by the active and the standby master controllers in the example network. Table 2 Master Controller Licensing in the Example Network License Capacity rc1-sunnyvale-3600 master controller (preferred active controller) Capacity rc2-sunnyvale-3600 master controller (preferred standby controller) AP Capacity PEF-NG RFProtect NOTE The PEFV license is required for every controller in the network that terminates VIA clients. The PEFV license is purchased as a single license that enables the functionality up to the full user capacity of a controller. Certificates The Aruba controller comes with a default server certificate. This certificate demonstrates the secure login process of the controller for captive portal, secure shell (SSH), and WebUI management access. This certificate is not for use in a production network. Aruba strongly recommends that you replace this certificate with a unique certificate that is issued to the organization or its domain by a trusted certificate authority (CA). To receive a custom certificate from a trusted CA, generate a Certificate Signing Request (CSR) on the controller and submit it to the CA. After you receive the digitally signed certificate from the CA, import it to the controller. For more details about generating the CSR and importing certificates, see Managing Certificates in the ArubaOS 6.1 User Guide available on the Aruba support site. Aruba Networks, Inc. All-Master Design for Remote Networks 22

23 Chapter 5: VLAN Design and Recommendations On an Aruba controller at the aggregation layer, VLANs are used in two logically different places: the access side of the controller where the APs terminate their GRE tunnels the user access side VLANs are used on the access side of the controller where the APs terminate their GRE tunnels. These VLANs carry traffic between the APs and the controllers. In Aruba VBN networks, the RAPs and VIA connect to the controller through a WAN link. After the initial authentication of the RAPs and VIA, they are assigned an inner IP address. This IP address is assigned from the address pool specified in the VPN server configuration of the controller. For details on configuring VPN server on the controller, see Chapter 7: Configuring VPN Server on the Controller. The controller assigns the inner IP address from the configured pool, so the IP subnets or VLANs defined in this pool must be managed by the controller and these subnets do not require DHCP services. Make sure that the DHCP services are disabled for the IP subnets used in the VPN address pool. In addition to these requirements, the VLANs used in the VPN address pool should be a part of a routable corporate subnet. VLANs are also used on the user access side. On the user access side, user VLANs exist and traffic flows to and from the users. During authentication, a process that is called role derivation assigns the proper VLAN to each user and forwards traffic to the wired network if allowed. For remote networks, the controller in the DMZ or the core switch in the internal network can be made the default gateway for user VLANs. If the DMZ controllers are used as the gateway, the VLAN design recommendations are these: Configure Virtual Router Redundancy Protocol (VRRP) for each user VLAN used between a pair of master controllers configured in active-standby redundancy. For details on the active-standby redundancy supported by the master controllers, see Chapter 6: Redundancy. Use distinct user VLANs for each pair of controllers. In other words, the user VLANs should be unique to a pair of redundant controllers because it is always important to restrict the broadcast domain to a single pair of redundant master controllers. Use a corporate DHCP server to provide DHCP services for the corporate employee networks. Ensure that the user VLANs are routable from the internal network. Ensure that the subnets used for VPN address pool are routable from the internal network else the VIA clients will not be able to reach corporate destinations and vise-versa. When captive portal authentication is required at remote sites, the controllers must be the default gateway and DHCP server for the guest VLAN. For details on configuring captive portal authentication at remote sites, see Chapter 14: Configuring the Guest Roles and VAP Profile for Micro Branch Office Deployments. Static routing or Open Shortest Path First (OSPF) can be enabled between the DMZ controllers and the core switch to achieve the required routing. Using OSPF simplifies the configuration. OSPF injects a route only for those VLANs whose operational state is up. The presence of a user on a VLAN changes its operational state to up. However, the operational state of the VLAN used in the VPN address pool for RAPs and VIA is not changed to the up state by the presence of a RAP or VIA client. If you need OSPF to inject routes for VLANs that are used as the VPN Aruba Networks, Inc. VLAN Design and Recommendations 23

24 address pool, manually change their operational state to up. Alternatively, static routes can be used for these VLAN. In an active-standby redundancy model, OSPF routes are injected only by the master of the VRRP instance If the core switch is used as the gateway, the VLAN design recommendations are these: Ensure user VLAN redundancy at the core layer. This can be achieved by using VRRP or any other proprietary technology supported by the core switches. Use distinct user VLANs for each pair of controllers because it is always important to restrict the broadcast domain to a single pair of redundant master controllers. Ensure that the subnets used for the VPN address pool are routable from the internal network. If they are not, the VIA clients will not be able to reach corporate destinations and vise-versa. When captive portal authentication is required at remote sites, the controllers must be the default gateway and DHCP server for the guest VLAN. Static routing or OSPF can be enabled between the DMZ controllers and the core switch to have the required accessibility to the VPN address pool. OSPF injects a route only for those VLANs whose operational state is up. The operational state of the VLAN used in the VPN address pool for RAPs and VIA is not changed to the up state by the presence of a RAP or VIA client. If you need OSPF to inject routes for VLANs that are used as the VPN address pool, manually change their operational state to up. Alternatively, static routes can be used for these VLAN. In an active-standby redundancy model, OSPF routes are injected only by the master of the VRRP instance. CAUTION The DHCP services are not synced between the active and standby controller. So do not use the master controller as the DHCP server for the employee network. CAUTION If multicast services are required between the corporate headquarters and the remote sites, then the controller must not be the default gateway. In this situation, the upstream router that has multicast routing support should be the default gateway. Aruba Networks, Inc. VLAN Design and Recommendations 24

25 VLAN Pooling The Aruba VLAN pooling feature allows a set of VLANs to be assigned to a designated group of users. VLAN pooling is tied to the virtual AP (VAP). Each VAP on a physical AP can have different VLANs or VLAN pools. VLAN pooling is supported only on tunnel and bridge mode VAPs. VAPs and wired ports in split-tunnel mode, which is the most common forwarding mode in remote deployments, do not support VLAN pooling. For more details about VLAN pooling, see the Aruba Mobility Controllers. Mobility controller VLANs 150, 151, 152, 153, 154 arun_049 arun_0359 Figure 8 VLAN pools distribute users across VLANs RAPs extend the corporate Layer 2 network to remote sites. By default, extending a Layer 2 VLAN to a remote location might increase the WAN bandwidth consumption by flooding the broadcast traffic on that VLAN to the remote site. The ArubaOS has several features to limit the flood of broadcast and multicast traffic. For information and recommendations on these features, see Appendix D: Broadcast and Multicast Mitigation Features. WAN bandwidth consumed by broadcast and multicast floods can be further reduced by the use of small IP subnets for user VLANs. In RAP deployments, Aruba recommends the use of small user VLANs (a VLAN for every remote devices), whenever possible. Network administrators can achieve this by creating a separate AP group, which does not share its user VLANs with other AP groups, for each set of RAPs that serve a total of remote Aruba Networks, Inc. VLAN Design and Recommendations 25

26 devices. Though this design increases the number of AP groups and access VLANs, it greatly minimizes the WAN bandwidth consumed by broadcast and multicast floods. CAUTION In VLAN pooling, a user is placed into a particular VLAN based on the output of a hash algorithm that uses the media access control (MAC) address of the client. VLANs assigned based on the hashing algorithm cannot be known before connecting to the network. In networks that use VLAN pooling, the clients with static IP addressing might not work because of the possible mismatch between the statically assigned IP and the VLAN assigned by the hashing algorithm. To avoid the possibility of a mismatch in the IP and VLAN configuration, Aruba recommends that static IP addressing should not be used when VLAN Pooling is enabled. The example network uses the DMZ master controllers as the default gateway for the user VLANs and VRRP is enabled for all user VLANs. OSPF is enabled on the DMZ controllers. The VPN address pool used for RAPs is routable from the internal network. The corporate DHCP server is used to provide DHCP services to the VLANs used for employee network. Table 3 lists the VLANs that are used in the example network. Table 3 VLANs in the Example Network VLANs IP subnet DHCP Server VLANs /24 static IP Used for management interface of controllers /24 corporate DHCP server Used for spit-tunnel VAPs and wired ports in a fixed telecommuter deployment /24 Used for VPN address pool / 24 Represents the DMZ interface of the controllers /24 RAP RAP DHCP server VLAN (configured in AP system Profile). Used for the guest network in fixed telecommuter deployments / 24 (rc1- sunnyvale-3600) /24 (rc2-sunnyvale-3600) Controller Used for guest networks, which provide captive portal authentication, in micro branch office deployments. For details, see Chapter 14: Configuring the Guest Roles and VAP Profile for Micro Branch Office Deployments. Aruba Networks, Inc. VLAN Design and Recommendations 26

27 Chapter 6: Redundancy Aruba offers several redundancy models for controller redundancy. The Aruba redundancy solutions can be implemented using VRRP or backup local management switch (LMS) IP. Use VRRP, which operates at Layer 2, for redundancy whenever possible. For more details about the various redundancy models and when to use backup LMS IP, see the Aruba Mobility Controllers Validated Reference Design. Master Redundancy To achieve high availability of the master controller, use the master redundancy model. In this scenario, two controllers are used: one controller is configured as the active master and the other controller acts as standby master. This setup is known as active-standby redundancy. The two controllers run a VRRP instance between them and the database and RF planning diagram is synchronized periodically. The synchronization period is a configurable parameter with a recommended setting of 30 minutes between synchronizations. Aruba recommends active-standby redundancy for the master controllers in the DMZ. DMZ Master active VRRP keepalives Periodic synchronization Master standby arun_0486 Figure 9 Active-standby redundancy In this configuration, one controller is always the active master controller and the other is always the standby master controller. When the active controller fails, the standby controller becomes the active master. Aruba controllers support other redundancy models. For more details, see the Aruba Mobility Controllers. In remote networks, the master controllers are in the DMZ and they can be deployed as the default gateway for the user VLANs. In this case, the master controllers have multiple VRRP instances. Each VRRP instance between two controllers determines which controller is the master of that VRRP instance. However, the actual master redundancy, which is the process of electing the master and the backup controller in the active-standby redundancy model, is based on the state of a single VRRP Aruba Networks, Inc. Redundancy 27

28 instance chosen for the purpose. The example network uses active-standby redundancy and has multiple VRRP instances, such as those for internal network, DMZ network, and user VLANs. NOTE The database synchronization synchronizes details such as the AP groups, user roles, profiles, server groups, and internal database to the backup controller. However, details such as the VLAN, IP parameters, VPN address pools, DHCP server parameters and licenses are not synched during database synchronization. Routing parameters such as OSPF and static routes are also not synched during database synchronization. The network administrators should configure these parameters on both the active and standby controllers. Between redundant controllers deployed in the active-standby redundancy model, it is important to ensure that one controller remains the master of all the VRRP instances at any given time. Network administrators can track the priority of the VRRP instances between controllers to ensure that one controller remains the master of all the VRRP instances. ArubaOS allows you to track VRRP based on these parameters: Time: When a VRRP instance A is tracked based on time, the priority of that VRRP instance can be increased by X for every Y minutes. Time-based tracking is used whenever only one VRRP instance is between the redundant controllers. State of another VRRP instance: When VRRP instance A is tracked based on the state of VRRP instance B, the priority of VRRP instance A can be increased by X if VRRP instance B is the master. VRRP tracking based on the state of another VRRP instance is used whenever multiple VRRP instances exist between redundant controllers. State of a VLAN ID: When VRRP instance A is tracked based on the state of a VLAN ID, the priority of VRRP instance A can be decreased by X if that VLAN ID is the operationally down. VRRP tracking based on the state of a VLAN ID is used whenever multiple VRRP instances exist between redundant controllers. The operational state of a VLAN is up if the associated physical port is up or if a user is on that VLAN. However, the VLAN used as the controller IP is up even if the associated physical port is down and no users are on that VLAN. State of a physical interface: When VRRP instance A is tracked based on the state of a physical interface, the priority of VRRP instance A can be decreased by X if the operational state of that physical interface is down. VRRP tracking based on the state of a physical interface is used whenever multiple VRRP instances exist between redundant controllers. In the example network, all the VRRP instances are tracked based on the state of VRRP-172, which is the VRRP instance between the interfaces connected to the external firewall. Preemption is disabled on VRRP-172 but is enabled on all the tracked interfaces. The master redundancy is determined based on VRRP-131. Aruba Networks, Inc. Redundancy 28

29 Table 4 through Table 7 summarize the VRRP instances and the database synchronization used for master redundancy in the example network. Table 4 Master Redundancy Setup VRRP ID VRRP IP Active Controller Standby Controller Enable Router Preemption Tracking VRRP Master State ID Tracking VRRP Master State Priority rc1-sunnyvale-3600 (priority 110) rc1-sunnyvale-3600 (priority 110) rc1-sunnyvale-3600 (priority 110) rc2-sunnyvale-3600 (priority 100) rc2-sunnyvale-3600 (priority 100) rc2-sunnyvale-3600 (priority 100) enabled enabled disabled Table 5 Master Redundancy Setting on rc1-sunnyvale-3600 Master-VRRP Peer s IP Address Peer s IPsec Key ********** Table 6 Master Redundancy Setting on rc2-sunnyvale-3600 Master-VRRP Peer s IP Address Peer s IPsec Key ********** Table 7 Database Synchronization Parameters Enable Periodic Database Synchronization Database Synchronization Period in Minutes enabled 30 enabled Include RF Plan Data Aruba Networks, Inc. Redundancy 29